Valve timing controller

ABSTRACT

A valve timing controller includes a housing, a vane rotor, a bush fixed to the vane rotor so as to support the housing in a relatively rotatable state, a coil spring provided to the bush and a retainer contacting the coil spring at least one point in the cross-section perpendicular to a rotation axis direction. The coil spring has a first end engaged with the vane rotor and a second end engaged with the housing. The retainer retains an axis of the coil spring to be kept parallel with the rotation axis direction.

CROSS REFERENCE TO RELATED APPLICATION

This application is based on Japanese Patent Application No. 2012-49305 filed on Mar. 6, 2012, the disclosure of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to a valve timing controller.

BACKGROUND

JP-11-132014A (U.S. Pat. No. 6,039,016) describes a valve timing controller which controls valve timing of an intake valve or an exhaust valve of an internal combustion engine. The valve timing controller has an advance oil pressure chamber and a retard oil pressure chamber between a vane rotor and a housing which have relative rotation with each other. The valve timing controller further has a torsion spring which generates a relative rotation phase between the vane rotor and the housing.

For example, the torsion spring generates a torque biasing the vane rotor to rotate in an advance direction relative to the housing. The valve timing controller produces a phase difference between the vane rotor and the housing by controlling the pressure of hydraulic fluid, corresponding to the torque of the torsion spring, so as to control the valve timing of the intake valve or the exhaust valve.

Because both ends of the torsion spring are inclined relative to a plane which is perpendicular to the rotation axis direction, the center axis of the torsion spring may be inclined relative to the rotation axis direction when the torsion spring is secured to the valve timing controller. In this case, a load generated by the torque of the torsion spring is also inclined relative to the rotation axis direction. If the housing is inclined to the vane rotor in the rotation axis direction, a wearing is easily generated between the vane rotor and the housing. Moreover, if the torsion spring is inclined relative to the rotation axis direction, assembling of components such as fitting bolt may become difficult when the valve timing controller is manufactured.

SUMMARY

It is an object of the present disclosure to provide a valve timing controller in which a vane rotor and a housing are restricted from having inclination relative to each other.

According to an example of the present disclosure, a valve timing controller that opens and closes an intake valve and an exhaust valve by rotating a driven shaft using a driving force of a driving shaft of an internal combustion engine and that controls open and close timing of at least one of the intake valve and the exhaust valve by changing a rotation phase between the driving shaft and the driven shaft includes a housing, a vane rotor, a bush, a coil spring, and a retainer. The housing rotates with one of the driving shaft and the driven shaft. The vane rotor rotates with the other of the driving shaft and the driven shaft, and has a vane accommodated in an accommodation chamber defined in the housing. T rotation phase of the vane rotor relative to the housing is changed using a pressure of hydraulic fluid supplied to a pressure chamber defined by partitioning the accommodation chamber with the vane. The cylindrical bush is fixed to the vane rotor, and supports the housing in a relatively rotatable state. The coil spring is provided to the bush and has a first end engaged with the vane rotor and a second end engaged with the housing. The coil spring generates a biasing torque biasing the vane rotor to rotate relative to the housing. The retainer contacts the coil spring at least one point when projected to a plane perpendicular to a rotation axis direction. The retainer retains a posture of the coil spring to be kept parallel with the rotation axis direction.

Accordingly, when the coil spring contacts the retainer, the center axis of the coil spring becomes parallel with the rotation axis direction, thus the posture of the coil spring is retained to be parallel with the rotation axis direction. Therefore, when the housing and the vane rotor rotate relative to each other due to the torque of the coil spring, the torque of the coil spring becomes perpendicular to the rotation axis direction. Thus, relative inclination in the rotation axis direction can be reduced between the housing and the vane rotor, and wearing can be reduced between the housing and the vane rotor.

Moreover, the coil spring is restricted from displacing in the radial direction, so components located adjacent to the coil spring can be flexibly arranged.

Furthermore, because the retainer and the coil spring contact with each other at the point, the contact area between the retainer and the coil spring can be reduced compared with a case where the retainer and the coil spring contact with each other on a plane. Accordingly, the friction resistance between the retainer and the coil spring can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings:

FIG. 1 is a schematic view illustrating a valve timing controller according to a first embodiment;

FIG. 2 is a schematic view illustrating a power train system having the valve timing controller of the first embodiment;

FIG. 3 is a schematic cross-sectional view taken along a line III-III of FIG. 1;

FIG. 4 is a schematic side view seen from a direction IV of FIG. 1;

FIG. 5 is a schematic cross-sectional view illustrating a bush and a coil spring of the valve timing controller of the first embodiment;

FIG. 6 is a schematic cross-sectional view illustrating a valve timing controller according to a second embodiment;

FIG. 7 is a schematic side view seen from a direction VIII of FIG. 6;

FIG. 8 is a schematic side view illustrating a valve timing controller according to a third embodiment;

FIG. 9 is a schematic cross-sectional view taken along a line IX-O-P-Q-IX of FIG. 8; and

FIG. 10 is a schematic side view illustrating a valve timing controller according to a fourth embodiment.

DETAILED DESCRIPTION

Embodiments of the present disclosure will be described hereafter referring to drawings. In the embodiments, a part that corresponds to a matter described in a preceding embodiment may be assigned with the same reference numeral, and redundant explanation for the part may be omitted. When only a part of a configuration is described in an embodiment, another preceding embodiment may be applied to the other parts of the configuration. The parts may be combined even if it is not explicitly described that the parts can be combined. The embodiments may be partially combined even if it is not explicitly described that the embodiments can be combined, provided there is no harm in the combination.

First Embodiment

A valve timing controller 1 according to a first embodiment will be described with reference to FIGS. 1 to 5. The valve timing controller 1 is, for example, an oil-pressure control type controller which uses oil as working hydraulic fluid.

As shown in FIG. 2, the valve timing controller 1 is applied to a roller locker type power train system of an engine 91, in which a chain 97 is engaged with a gear 93 fixed to a crankshaft 92, a gear 115 fixed to a camshaft 94, and a gear 96 fixed to a camshaft 95. The crankshaft 92 may correspond to a driving shaft, and the camshaft 94, 95 may correspond to a driven shaft. Driving force is transmitted to the camshafts 94 and 95 from the crankshaft 92. The camshaft 94 opens and closes an exhaust valve 99 via a cam mechanism, and the camshaft 95 opens and closes an intake valve 98 via a cam mechanism. The valve timing controller 1 of the first embodiment controls the opening and closing timing of, for example, the exhaust valve 99.

The valve timing controller 1 will be described hereinafter with reference to FIGS. 1-5. FIG. 1 illustrates a cross-sectional view of the valve timing controller 1 corresponding to a line I-O-P-Q-I of FIG. 4. The valve timing controller 1 is arranged inside a cover of the engine 91, and has a housing 10, a vane rotor 20, a bush 31, a coiled spring 40, and a retainer 51.

The housing 10 has a sprocket 11, a shoe housing 12 formed into a cylinder shape, and a front plate 13 formed into a disc shape. The shoe housing 12 and the front plate 13 are integrated with each other.

The sprocket 11, the shoe housing 12, and the front plate 13 are coaxially fixed using a bolt, and the shoe housing 12 is located between the front plate 13 and the sprocket 11.

The sprocket 11 has a board shape, and the gear 115 is defined on the outer circumference of the sprocket 11. The sprocket 11 is linked with the crankshaft 92 through the chain 97. When a driving force is transmitted from the crankshaft 92 to the sprocket 11, the housing 10 rotates together with the crankshaft 92 in an advance (clockwise) direction X in FIG. 3.

As shown in FIG. 3, the shoe housing 12 has shoes 121, 122, 123, 124 (referred as 121-124) arranged in the rotational direction with a regular interval and projected inward in the radial direction from the inner circumference wall of the shoe housing 12. The projection end surface of the shoe 121-124 has an arc-shape, and is slidably contact with an outer surface of a boss portion 25 of the vane rotor 20. A seal member 125 is fitted to a concave portion of the shoe 121-124. Accommodation chambers 100 are defined between the adjacent shoes 121-124 respectively. Each of the accommodation chambers 100 is surrounded by the side face of the corresponding shoe 121-124 and the inner circumference wall surface of the shoe housing 12, and has a sector shape shown in FIG. 3.

The vane rotor 20 is accommodated in the housing 10. As shown in FIG. 1, the axial end of the vane rotor 20 is slidingly contact with the wall surface of the sprocket 11 adjacent to the vane rotor 20, and the other axial end of the vane rotor 20 is slidingly contact with the wall surface of the front plate 13 adjacent to the vane rotor 20. As shown in FIG. 3, the vane rotor 20 has vanes 21, 22, 23, 24 (referred as 21-24) in addition to the boss portion 25.

The vanes 21-24 are arranged in the rotational direction with a regular interval and projected from the outer circumference of the boss portion 25 to be accommodated in the accommodation chambers 100 respectively. The projection end surface of the vane 21-24 has an arc-shape, and is slidably contact with the inner surface of the shoe housing 12. A seal member 26 is fitted to a concave portion defined in the projection end surface of the vane 21-24. The vane 21-24 partitions the corresponding accommodation chamber 100, thereby defining an advance oil pressure chamber 101, 102, 103, 104 (referred as 101-104) and a retard oil pressure chamber 105, 106, 107, 108 (referred as 105-108), which may correspond to a pressure chamber.

The advance oil pressure chambers 101-104 communicate with advance passages 111, 112, 113, 114 (referred as 111-114) defined in the sprocket 11, respectively. The advance passages 111-114 communicate with an advance passage 62, as shown in FIG. 1.

The retard oil pressure chambers 105-108 communicate with retard passages 201, 202, 203, 204 (referred as 201-204) defined in the vane rotor 20, respectively. The retard passages 201-204 communicate with a retard passage 63.

As shown in FIG. 1, a stopper piston 27 is accommodated to slidably reciprocate in the vane 21. The stopper piston 27 is fitted to a fitting ring 117 arranged in the sprocket 11 by a biasing force of a helical compression spring 29, thereby restraining the vane rotor 20 to the maximum advance position relative to the housing 10. On the other hand, the stopper piston 27 is displaced to separate from the fitting ring 117 by at least one of an oil pressure force supplied from the retard oil pressure chamber 105 through a passage 221 and an oil pressure force supplied from the advance oil pressure chamber 101 through a passage 222 against the biasing force of the helical compression spring 29, thereby allowing the vane rotor 20 to have relative rotation.

The bush 31 is fitted to the boss portion 25, and is coaxially inserted to the inner circumference side of the front plate 13 in the rotatable state relative to the front plate 13. The boss portion 25 of the vane rotor 20 is fixed to the camshaft 94 together with the bush 31 using a bolt 70. The vane rotor 20 and the camshaft 94 rotate in the clockwise rotation in FIG. 3. The vane rotor 20 is rotatable relative to the housing 10 together with the camshaft 94.

In FIG. 3, the advance direction X represents an advance rotation direction of the vane rotor 20 relative to the housing 10, and a retard direction Y represents a retard rotation direction of the vane rotor 20 relative to the housing 10. FIG. 3 illustrates a state where the vane rotor 20 is located at the maximum advance position at which the vane rotor 20 is restricted from having rotation in the advance direction X and is allowed to have rotation in the retard direction Y relative to the housing 10.

The bush 31 has a based cylindrical shape, and has a cylinder (pipe) part 311 and a bottom wall 312. The cylinder part 311 has an opening part opposite from the bottom wall 312, and a notch 36 is defined in the cylinder part 311 adjacent to the opening part. The bottom wall 312 has a through hole 35, and integrally has an inside guide 38 projected toward the opening part from an edge of the through hole 35. The inside guide 38 is formed coaxially with the bush 31. As shown in FIG. 4, a positioning slot 381 is defined in the inside guide 38. The bush 31 is fitted to the boss portion 25 of the vane rotor 20, and is fixed with the bolt 70 which penetrates the through hole 35.

The coiled spring 40 has a cylindrical shape, and includes a main part 41, a first end 42 and a second end 43. The first end 42 is formed on the inner side of the main part 41 in the radial direction, and the second end 43 is formed on the outer side of the main part 41 in the radial direction. The coiled spring 40 is accommodated in the bush 31, and the first end 42 is engaged with the positioning slot 381 of the inside guide 38. The second end 43 of the coiled spring 40 is taken out from the notch 36 of the bush 31 outward in the radial direction, and is engaged with a spring hook 131 fixed to the front plate 13. Therefore, the first end 42 rotates with the vane rotor 20, and the second end 43 rotates with the housing 10. Moreover, the coiled spring 40 applies a force rotating the vane rotor 20 in the advance direction X relative to the housing 10 as a biasing torque.

The retainer 51 will be explained based on FIGS. 4 and 5. The retainer 51 has two projection parts 511 arranged in the circumference direction of the bush 31. The projection part 511 projects from the inner wall of the cylinder part 311 of the bush 31 inward in the radial direction, and has a rib shape extending in the axial direction. In the present embodiment, the projection part 511 and the bush 31 are integrally formed. The projection part 511 has a contact part 512 extending in parallel with a rotation axis direction O. For example, the contact part 512 is defined by a ridge line portion of the projection part 511.

When the coiled spring 40 is accommodated in the bush 31, the outer wall of the main part 41 is contact with the contact part 512 of the retainer 51 and the inner wall of the cylinder part 311 of the bush 31. That is, as shown in FIG. 4, the retainer 51 is contact with the coiled spring 40 at two points in the cross-sectional view of FIG. 4, for example, when the retainer 51 is projected on a plane surface perpendicular to the rotation axis direction O. In other words, the two contact parts 512 formed to extend in parallel with the rotation axis direction O are contact with the coiled spring 40.

A controller 60 will be described with reference to FIG. 1. The controller 60 includes a switch valve 61 and an electronic control unit (ECU) 80. The switch valve 61 is connected with the advance passage 62, the retard passage 63, a pump passage 64, and drain passages 65 and 66. An oil pump 67 is installed in the pump passage 64. The oil pump 67 pumps oil corresponding to working fluid from an oil tank 68 through the upstream of the pump passage 64, and discharges oil toward the switch valve 61 through the downstream of the pump passage 64. Oil is discharged through the drain passage 65, 66 toward the oil tank 68 from the switch valve 61.

The ECU 80 is constructed by an electric circuit such as microcomputer, and is electrically connected with plural sensors such as cam angle sensor 81, crank angle sensor 82 in addition to the switch valve 61. The ECU 80 computes a real phase and a target phase as to the engine phase of the camshaft 94 relative to the crankshaft 92, based on the outputs of the sensors, and controls a drive electric current provided to the switch valve 61 according to the computed result so as to supply electricity to the switch valve 61.

The electric power supplied to the switch valve 61 is controlled by the ECU 80. The switch valve 61 is an electromagnetic spool type valve having a spool 613 which is moved in the axial direction according to balance between the driving force generated in a drive direction by activating an electromagnetic actuator 611 and a restoring force of a return spring 612 generated in an opposite direction opposite from the drive direction. The switch valve 61 switches the passage connection of the pump passage 64 and the drain passages 65 and 66 relative to the advance passage 62 and the retard passage 63 by the axial movement of the spool 613 according to the drive electric current provided to the actuator 611.

Operations of the valve timing controller 1 will be described hereinafter. When the engine 91 is stopped, the stopper piston 27 is fitted to the fitting ring 117 at the maximum advance position due to the biasing force of the helical compression spring 29.

At the engine startup time, the oil pump 67 is activated and the hydraulic fluid discharged from the oil pump 67 flows into the retard oil pressure chambers 105-108 via the retard passages 201-204. As a result, the stopper piston 27 receives the oil pressure from the retard oil pressure chamber 105 through the passage 221. When the oil pressure is raised to a predetermined pressure, the stopper piston 27 is separated from the fitting ring 117. Thereby, the vane rotor 20 and the housing 10 become rotatable relative to each other.

A retard operation will be described. The ECU 80 controls the energizing of the switch valve 61, thereby switching the connection state of the advance passage 62 and the retard passage 63 relative to the oil pump 67. As a result, when the retard passage 63 communicates with the oil pump 67, the oil pumped by the oil pump 67 flows into the retard oil pressure chambers 105-108 via the retard passage 63 and the retard passages 201-204. Moreover, at this time, the oil of the advance oil pressure chambers 101-104 is discharged via the advance passages 111-114 and the advance passage 62 to the oil tank 68. Thus, the oil pressure is impressed to the vanes 21-24 facing the retard oil pressure chambers 105-108, and the vane rotor 20 has relative rotation in the retard direction Y relative to the housing 10.

An advance operation will be described. When the advance passage 62 communicates with the oil pump 67, the oil pumped by the oil pump 67 flows into the advance oil pressure chambers 101-104 via the advance passage 62 and the advance passages 111-114. Moreover, at this time, the oil of the retard oil pressure chambers 105-108 is discharged via the retard passages 201-204 and the retard passage 63 to the oil tank 68. Thus, the oil pressure is impressed to the vanes 21-24 facing the advance oil pressure chambers 101-104, and the vane rotor 20 has relative rotation in the advance direction X relative to the housing 10.

Thus, the passage to which the hydraulic fluid is supplied from the oil pump 67 is switched, thereby controlling the oil pressure of the advance oil pressure chambers 101-104 and the oil pressure of the retard oil pressure chambers 105-108. Therefore, the relative rotation phase of the vane rotor 20 to the housing 10 is controlled so as to control the valve timing. In addition, at the valve timing control timing, the ECU 80 performs feedback control as to the energizing of the switch valve 61 in a manner that the actual valve timing of the exhaust valve 99 agrees with the target valve timing. Thus, the valve timing can be accurately controlled.

At the engine stop time, because the oil pump 67 is also stopped, the oil is no longer supplied to neither the advance passage 62 nor the retard passage 63. Then, according to the restoring force of the coiled spring 40, the vane rotor 20 has relative rotation to the maximum advance position, and the stopper piston 27 is fitted to the fitting ring 117.

For example, when the engine 91 is abnormally stopped by an engine failure etc., there is a case where the next re-startup is conducted while the stopper piston 27 is not fitted to the fitting ring 117. In such a case, the rotation phase is made to return to the default position at which the startup is possible by rotating the vane rotor 20 in response to the torque of the coiled spring 40 in the cranking period of the next re-startup time.

According to the first embodiment, the retainer 51 is in contact with the coiled spring 40 at the two points in the cross-section perpendicular to the rotation axis direction O. That is, the projection part 511 of the retainer 51 has the contact part 512 formed to extend in parallel with the rotation axis direction O. Thereby, when the coiled spring 40 contacts the contact part 51, the center axis Os of the coiled spring 40 becomes parallel with the rotation axis direction O. Therefore, when the housing 10 and the vane rotor 20 rotate relative with each other, the torque of the coiled spring 40 is applied perpendicular to the rotation axis direction O. For this reason, the relative inclination between the housing 10 and the vane rotor 20 can be reduced in the rotation axis direction O, and wear between the housing 10 and the vane rotor 20 can be reduced.

In the present embodiment, the retainer 51 has a plurality of the projection parts 511. That is, in the cross-section perpendicular to the rotation axis direction O, the retainer 51 is contact with the coiled spring 40 at the plural points. Thereby, because the projection parts 511 contact with the coiled spring 40 simultaneously, the effect correcting the posture of the coiled spring 40 can be raised so that the center axis Os of the coiled spring 40 and the rotation axis direction O become parallel with each other with more reliability.

In the present embodiment, the retainer 51 is arranged on the outer side of the coiled spring 40 in the radial direction. Therefore, a space can be secured on the inner side of the coiled spring 40 in the radial direction. Further, the bolt 70 can be attached easily on the inner side of the coiled spring 40 in the radial direction.

In the present embodiment, the retainer 51 and the bush 31 are integrally formed with each other. Thus, the number of components used for producing the valve timing controller 1 can be reduced.

Second Embodiment

A second embodiment will be described with reference to FIGS. 6 and 7. FIG. 6 is a schematic cross-sectional view taken along a line VI-O-P-Q-VI in FIG. 7. In the second embodiment, only a different portion different from the first embodiment is explained and the explanation about the same composition as the first embodiment is omitted. The same portion has the same reference number as the first embodiment, and the explanation is omitted.

In the second embodiment, the bush 32 is formed into a cylindrical shape, and has a cylinder (pipe) part 321 and a bottom wall 322. The cylinder part 321 has an engaging hole 37 on a side opposite from the bottom wall 322. An approximately center part of the bottom wall 322 has the through hole 35.

The retainer 52 has two projection parts 511 projected outward in the radial direction from the outer wall of the cylinder part 321 of the bush 32. The projection parts 511 are arranged in the circumference direction, and each of the projection parts 511 has a rib shape extending in the axial direction. In the present embodiment, the projection part 511 and the bush 32 are integrally formed. The projection part 511 has the contact part 512 formed to extend in parallel with the rotation axis direction O.

In the second embodiment, the coiled spring 40 is arranged on the outer side of the bush 32 in the radial direction. The first end 42 of the coiled spring 40 is engaged with the engaging hole 37 of the bush 32, and the second end 43 of the coiled spring 40 is engaged with the spring hook 131. Moreover, the inner wall of the main part 41 of the coiled spring 40 is contact with the contact part 512 of the retainer 52.

In the present embodiment, the retainer 52 is arranged on the inner side of the coiled spring 40 in the radial direction. Therefore, a space can be secured on the outer side of the coiled spring 40 in the radial direction. For example, when the covering 14 is attached to a position adjacent to the coiled spring 40, the attaching of the covering 14 is not affected by the coiled spring 40.

Third Embodiment

A third embodiment will be described with reference to FIGS. 8 and 9. FIG. 9 is a schematic cross-sectional view taken along a line IX-O-P-Q-IX in FIG. 8. In the third embodiment, only a different portion different from the first embodiment is explained and the explanation about the same composition as the first embodiment is omitted. The same portion has the same reference number as the first embodiment, and the explanation is omitted.

In the third embodiment, the bush 33 is formed into the cylindrical shape having the cylinder part 331 and the bottom wall 332. The notch 36 is defined in the cylinder part 331, and the through hole 35 and the inside guide 38 are defined in the bottom wall 332.

In the present embodiment, the retainer 53 has a bar shape, and is provided in the separate state separate from the bottom wall 332 of the bush 33. Moreover, the number of the retainers 53 is two, and the retainers 53 are arranged in the circumference direction so as to contact with the side wall of the cylinder part 331.

When the coiled spring 40 is accommodated in the bush 33, the outer wall of the main part 41 is contact in the contact part 512 of the retainer 53 and the inner wall of the cylinder part 311 of the bush 33.

In the present embodiment, the retainer 53 is provided separately from the bush 33. Thus, the shape of the bush 33 can be simplified, and the bush 33 can be manufactured with fewer processes.

Fourth Embodiment

A fourth embodiment will be described with reference to FIG. 10. In the fourth embodiment, only a different portion different from the second embodiment is explained and the explanation about the same composition as the second embodiment is omitted. The same portion has the same reference number as the second embodiment, and the explanation is omitted.

The bush 32 is formed into the cylindrical shape, and has the cylinder part 321 and the bottom wall 322. The cylinder part 321 has the engaging hole 37 on a side opposite from the bottom wall 322. An approximately center part of the bottom wall 322 has the through hole 35.

In the present embodiment, the retainer 53 is detachable from the front plate 13. Moreover, two of the retainers 53 are arranged in the circumference direction of the cylinder part 321. When the coiled spring 40 is provided to the bush 34, the outer wall of the main part 41 is in contact with the contact part 512 of the retainer 53. According to the fourth embodiment, the same advantages can be achieved as the second and third embodiments.

Other Embodiment

The valve timing controller is applied to the roller locker type power train system in the above embodiments. Alternatively, the valve timing controller may be applied to other type power train system such as direct compression type system.

The valve timing controller may be applied to the intake valve of the engine instead of the exhaust valve.

The vane rotor may be rotated with the crankshaft instead of the camshaft. In the above embodiments, in the cross-section perpendicular to the rotation axis direction, the retainer contacts the coiled spring at two points. Alternatively, the retainer may contact the coiled spring at one point, or three or more points in the cross-section perpendicular to the rotation axis direction.

The present application is not limited to the above embodiments.

Such changes and modifications are to be understood as being within the scope of the present disclosure as defined by the appended claims. 

What is claimed is:
 1. A valve timing controller that opens and closes an intake valve and an exhaust valve by rotating a driven shaft using a driving force of a driving shaft of an internal combustion engine, the valve timing controller controlling open and close timing of at least one of the intake valve and the exhaust valve by changing a rotation phase between the driving shaft and the driven shaft, the valve timing controller comprising: a housing rotating with one of the driving shaft and the driven shaft; a vane rotor rotating with the other of the driving shaft and the driven shaft, the vane rotor having a vane accommodated in an accommodation chamber defined in the housing, a rotation phase of the vane rotor relative to the housing being changed using a pressure of hydraulic fluid supplied to a pressure chamber defined by partitioning the accommodation chamber with the vane; a bush having a cylindrical shape and fixed to the vane rotor, the bush supporting the housing in a relatively rotatable state; a coil spring provided to the bush and having a first end engaged with the vane rotor and a second end engaged with the housing, the coil spring generating a biasing torque biasing the vane rotor to rotate relative to the housing; and a retainer contacting the coil spring at least one point in a cross-section perpendicular to a rotation axis direction, the retainer retaining an axis of the coil spring to be kept parallel with the rotation axis direction.
 2. The valve timing controller according to claim 1, wherein the retainer contacts the coil spring at plural points in the cross-section perpendicular to the rotation axis direction.
 3. The valve timing controller according to claim 1, wherein the retainer is located on an outer side of the coil spring in a radial direction.
 4. The valve timing controller according to claim 1, wherein the retainer is located on an inner side of the coil spring in a radial direction.
 5. The valve timing controller according to claim 1, wherein the retainer is integrally formed with the bush.
 6. The valve timing controller according to claim 1, wherein the retainer is fixed to the bush or the housing. 